Giovanni Palumbo has been charged with three counts of failure to comply with a court order and criminal harassment. He has pleaded not guilty to the charges.
Palumbo, a former doctor from Ottawa, has allegedly sent Twain a series of letters, showed up to her family cottage in Ontario and even attended her grandmother's funeral before being arrested at a Canadian awards ceremony earlier this year.
Defense lawyer Gary Barnes said Friday during Twain's cross-examination that Palumbo simply didn't realize that Twain wasn't interested.
But Twain, appearing via video from an undisclosed location, didn't see it that way.
"I'm torn emotionally because I have compassion for anybody who's reaching out in need - fans often do that.... I feel very sad ... and awkward having to go through these very personal matters with Mr. Palumbo because it's such an invasion of his privacy."
However, Twain said she still feels anxiety about Palumbo contacting her in the future.
As Twain recounted the contents of numerous letters allegedly sent to her by Palumbo, the former doctor leapt to his feet and addressed the court loudly.
"But I didn't know you received any of them - you understand?" yelled Palumbo, alluding to why he persisted in corresponding with Twain.
Amid his outburst, he muttered that the letters were meant to be "lighthearted." But Twain disagreed.
"It was scary and haunting," she said of one correspondence.
In court Thursday, Palumbo had a similar outburst declaring: "Eilleen, you can trust me, I'm going to plead guilty." Twain's real first name is Eilleen.
Palumbo has not yet changed his plea.
The Associated Press contributed to this report.